Vibrator



June 5, 1956 K. A. s. KARLSTRGM VIBRATOR Filed Feb. 19, 1953 J1me 1956 K. A. s. KARLSTROM VIBRATOR Filed Feb. 19, 1953 2 Sheets-Sheet 2 United States Patent VIBRATOR Karl Axel Sam Karlstriim, Gavle, Sweden Application February 19, 1953, Serial No. 337,848

Claims priority, application Sweden March 4, 1952 9 Claims. (Cl. 74-61) The present invention refers to vibrators of the type wherein the vibrations are generated by a rotating conical pendulum carrying a roll body rotating with the pendulum rod and running on a stationary inner or outer roll race, said pendulum being adapted to be driven by a shaft which is coupled or adapted to be coupled to the pendulum rod adjacent to the oscillation point thereof. The invention has for its object to provide a suitable mounting of the pendulum, and is principally distinguished by the feature that the pendulum is swingably mounted on the free end of an arm coaxial with the axis of oscillation of the pendulum and extending through the hollow pendulum rod in the longitudinal direction thereof, said arm being at the opposite end thereof secured in a cantilever fashion in a rigid part of the vibrator.

The invention will be described more closely with reference to the accompanying drawings which illustrate two different forms of embodiment of the vibrator. Fig. 1 is a plan view and Fig. 2 an elevation of the vibrating support or vibrating table in which is secured an impeller adapted to generate the vibrations. Fig. 3 shows a section on line IIIIII in Fig. 2, and Fig. 4 is a section on line IV-IV in Fig. 3. Fig. 5 shows the impeller in elevation and partly in section on a larger scale. Fig. 6 shows the second embodiment of the impeller in longitudinal section.

The vibrator shown in Figs. 1-5 consists of a support or vibrating table 1 for the mounting of the objects to be vibrated and of an impeller mounted in the same, said impeller being composed of two members 2, 3 in the example shown, the member 2 being secured in a conical bore in the one lateral Wall 4 of the vibrating table, whereas the other member 3, which is hollow, is loosely thrust over the free end of the member 2. The freely mounted members 2, 3 extend transversely through a space 8 defined by the lateral walls 4, 5, 6, 7 of the table, the member 3 projecting into a bore 9 in the wall 6. Inserted into this wall is a sleeve 10 adapted to serve as an attachment for a coupling sleeve by which the driving shaft is coupled to the end of the member 3. This member is provided with two claws 11, 12 forming one of the coupling members of a claw-coupling, through which the driving shaft is coupled to the member 3. The driving shaft is preferably constituted by a flexible spindle. To facilitate the fixing of the objects to be vibrated on the table 1, the latter is provided with holes 13, into which the objects may be inserted. In the use of the vibrator for dental purposes said objects may consist of tooth impressions into which amalgam or other material is introduced to be vibrated, the impressions being preferably surrounded by tubular sleeves to permit of being conveniently introduced into said holes. Contingently, the vibrating table may be formed into a vessel to be used in the vibrating process. In certain cases it might be found suitable to secure the object to be vibrated, such as an impression of a jaw or part of a jaw, on the table by means of a thermo-plastic mass, which is first attached to the impression and, while the mass is still soft, is then pressed into the holes in the table, Where it hardens and fixes the impression firmly.

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The member 2 of the impeller has the configuration of a cylindrical arm or pin, which is thrust with its conically shaped end portion 14 into the conical bore in the wall 4 so as to be immovably fixed relatively to the vibrating table. The member 3 consists of a hollow tubular part 3 formed at one end thereof into a cylindrical sleeve 15, which forms a roll body adapted to roll on a roll race 16 arranged on the arm 2. The inner diameter of the sleeve 15 is somewhat larger than the diameter of the roll race 16. The member 3 is swingably and rotatably mounted at the opposite end thereof on the spherical end 17 of a supporting pin 18 extending from the arm 2.

When the member 3 is caused to rotate by being coupled to the driving shaft, the sleeve 15 will roll on the roll race 16 and undergo a planetary motion relatively to the member 2 of the impeller so as to cause the latter to vibrate at a high frequency determined by the speed of revolution of the member 3 and the diiference between the inner diameter of the sleeve 15 and the diameter of the roll race 16. The member 3 will then swing as a pendulum about the spherical part 17, which then serves as a combined thrust and radial bearing.

On account of the arrangement of the contrivance described it will be possible to locate the bearing of the pendulum close to the coupling member 11, 12, the amplitude of the oscillations of such member becoming then inconsiderable. This arrangement also makes it possible to center the coupling member secured on the driving shaft by means of a center pin, which in its coupled position engages a central bore 19 in the pin 18, the pendulum rod being then provided with a corresponding recess 20.

In the embodiment shown in Fig. 6, the roll body 21 is adapted to roll on an outer roll race on the inside of a cylindrical sleeve 22 intended to be secured in a vibrating table. In this case the rounded end 23 of the arm 2 only serves as a journal in a radial bearing, the axial forces then acting on the pendulum being taken up by one of two ball bearings 24, 25, through which the arm 2 is rotatably secured in the sleeve 22. By the fact that the arm is thus rotatably mounted the friction will be reduced in the bearing 23, 26. During the rotary movement the roll body 21 bears with the outer end thereof against the race of the bearing 25 rotating with the arm 2, whereby the frictional resistance is reduced to a minimum.

A vibrator of the type described above may be used for a variety of purposes, for instance in the dental profession for vibrating amalgam or materials of the nature of plaster in the making of patterns. It may also be constructed without any plate attached to the same, the impeller 2 or 22 then permitting of being provided with tools of various kinds for working at vibrations, such tools consisting, for instance, of a spatula, chisel, knife, sliding trundle, impact drill or the like.

What I claim is:

1. A vibrator comprising, in combination, a vibratory body, a cantilever rod carried at one end in said vibratory body and having a bearing head at its opposite end, a sleeve-shaped rotary member surrounding said rod and arranged to swing as a conical pendulum about the longitudinal axis of said rod while being supported by said bearing head as a swinging center, a roll race firmly connected with the vibratory body, said rotary member ineluding a sleeve-shaped roll body arranged to roll on said roll race while undergoing a planetary motion about the axis of the cantilever rod, and a shaft coupling provided on the rotary member near the swinging center thereof.

2. A vibrator as defined in claim 1, wherein the roll race upon which the roll body is adapted to roll is provided on the cantilever rod.

3. A vibrator as defined in claim 1, wherein the cantilever rod is non-rotatably and rigidly connected with the vibratory member.

4. A vibrator as defined in claim 3, wherein the vibratory body is provided with a conical aperture and said cantilever rod has a conical end portion received in said conical aperture in the vibratory body.

5. A vibrator as defined in claim 3, wherein the bearing head of the cantilever rod forms the stationary part of a combined axial and radial bearing.

6. A vibrator as defined in claim 1, wherein the cantilever rod is rotatably mounted in the vibratory member.

7. A vibrator as defined in claim 6, wherein the cantilever rod is journalled in a bearing forming a thrust hearing for the roll body adapted to take up the pressure of the axial forces acting upon the rotary member.

8. A vibrator as defined in claim 7, wherein the rotary member and the cantilever red are arranged inside a sleeve providing the outer roll race for the roll body.

9. A vibrator as defined in claim 1, wherein the bearing head of the cantilever rod is provided with an axial bore for receiving a centering pin when the rotary member is coupled to a driving shaft.

References Cited in the file of this patent UNITED STATES PATENTS 2,194,410 Svensen Mar. 19, 1940 2,219,348 Turner Oct. 29, 194-0 2,422,639 Wenander June 17, 1947 2,430,817 Jackson Nov. 11, 1947 2,437,983 Wenander Mar. 16, 1948 2,546,806 Wenander Mar. 27, 1951 2,649,286 Karlstrom Aug. 18, 1953 

